Computer printers are often provided with a wide variety of paper trays or sources. The wide variety of paper sources alleviates the necessity for users to constantly have to change the paper trays. This feature is especially convenient on computer networks having multiple computers where multiple computer users may each require a different paper source.
The multiple computers each have either a printer driver or application for driving the computer printer on the network. The printer driver or application sends commands to the network printer including a command for selecting a paper source. The printer control commands are in a printer control language known as PCL. A PCL select paper feed command is used to request a particular one of the paper sources on a given printer. The parameter, i.e., number used in the PCL select paper feed command to select comparable sources often varies among printers. The use of different numbers in the PCL select paper feed commands causes problems when an existing network printer is replaced with a replacement network printer unless printer drivers or applications are changed or custom firmware changes in the printer are made. These changes are not always possible or desirable. A customer may decide not to purchase a printer if the purchase of the replacement printer requires new printer drivers to be installed. The custom firmware may be difficult to change because the programmer who created the custom firmware is no longer available, and if the firmware can be changed, it might be expensive.
An example of source number assignments for an existing printer (Hewlett-Packard Laser Jet 5Si) and for a replacement printer (Lexmark Optra S 2450) is described for a network as depicted in FIG. 1. The network N includes a computer printer P, a first computer A and a second computer B. The computer printer in this example is an Optra S 2450 model printer. Installed in computer A is a printer driver for the Hewlett-Packard Laser Jet 5Si model printer. Installed in computer B is a custom application having its own printer driver for driving the Hewlett-Packard Laser Jet 5Si model printer. For example, the Hewlett-Packard Laser Jet model printer 5Si uses the following source number assignments for the following paper sources having the listed paper capacities.
TABLE A ______________________________________ Hewlett-Packard Laser Jet 5Si Tray Number Source Number Capacity ______________________________________ Tray 1 Source Number Assignment 8 100 Tray 2 Source Number Assignment 1 500 Tray 3 Source Number Assignment 4 500 Tray 4 Source Number Assignment 5 2000 ______________________________________
In this example, the new replacement printer (Lexmark Optra S 2450) has the following source number assignments for the following paper sources:
TABLE B ______________________________________ Lexmark Optra S 2450 Tray Number Number Capacity ______________________________________ Tray 1 Source Number Assignment 1 250 Tray 2 Source Number Assignment 4 500 Tray 3 Source Number Assignment 5 500 Tray 4 Source Number Assignment 20 2000 ______________________________________
As is evident from the above tables, compatibility problems have been created because the replacement printer has different source number assignments than the existing printer being replaced. Thus, without printer driver changes, when the replacement printer receives a PCL print request code including the source number assignment, the wrong paper source would be selected. This problem has been previously addressed with a limited degree of success.
A previous known method changed source number assignments using printer job language (PJL) commands. The PJL commands modify tray renumber printer settings to change source number assignments for a paper source. The following tray renumber printer settings were used:
1) Tray 1 Renumber; PA1 2) Multi-Purpose Feeder Renumber; and PA1 3) Last Tray Renumber. PA1 1. Tray 1 Renumber PA1 2. Multi-Purpose Feeder Renumber PA1 3. Last Tray Renumber PA1 Source 1 (Main Paper Source)=Upper Cassette (on the Laser Jet 5, the Upper Cassette is identified as Tray 2. PA1 Source 4 (Alternate Paper Source)=Multi-Purpose Tray (on the Laser Jet 5, the Multi-Purpose Tray is identified as Tray 1. PA1 Source 5 (Optional Source)=Optional Lower Cassette (on the Laser Jet 5, the Optional Lower Cassette is identified as Tray 3. PA1 Source 1 (Main Paper Source)=Tray 1. PA1 Source 4 (Alternate Paper Source)=Tray 2. PA1 Source 8 (Tray 1-Right Side)=Multi-Purpose Feeder.
In this previous known method, a swap of source assignment occurs as explained below in the following example.
Last Tray Renumber Example
This example uses the last tray renumber function. The printer has optional sources Tray 2, Tray 3 and Tray 4 installed. Using a PJL command, last tray renumber is equal to Tray 3 and, as a result, the source assignments for Tray 3 and Tray 4 are swapped.
Tray 3
Tray 4
All other source assignments are unchanged. The 2000 sheet capacity source is accessed using source number 5 for both the Laser Jet 5Si and Optra S 2450.
Using Multiple Renumbering Settings
Two or more of the withdrawn settings may be used together to obtain more variations of source assignment swapping.
When more than one of the renumber settings is utilized, the order used by PCL when processing the renumber settings is relevant and must remain constant to achieve consistent results. The renumbering functions are processed in the following order.
An example of multiple renumbering using a Lexmark Optra S 1650 to replace a Hewlett-Packard Laser Jet 5 is explained below. The Hewlett-Packard Laser Jet 5 has the following source assignments for the following paper sources as listed in Table C below:
TABLE C ______________________________________ Hewlett-Packard Laser Jet 5 Tray Number Source Number Assigmnent ______________________________________ 1 4 2 1 3 5 ______________________________________
The Hewlett-Packard Laser Jet 5 has only three paper sources installed:
The replacement Lexmark Optra S 1650 has the following source assignments for the following paper sources as listed in Table D below:
TABLE D ______________________________________ Lexmark Optra S 1650 Source Source Number Renumbered Number Assignment Source (after Factory Assignment (after Last Tray) Last Tray Source (after MPF Renum = T3 Renum = T3 Tray Number Renum = and MPF and MPF Number Assignment T2) Renum = T2) = Renum = T2) ______________________________________ 1 1 1 1 T1 2 MPF 3 T2 MP 8 5 Feeder ______________________________________
The Lexmark Optra S 1650 has the following three paper sources installed:
To make the Lexmark Optra S 1650 compatible with the Hewlett-Packard Laser Jet 5 using a PJL command, the multi-purpose feeder renumber is equal to Tray 2, and as a result, the source assignments for the multi-purpose feeder and Tray 2 are swapped. This swap is illustrated in the third column of Table D. Then using a PJL command, the last tray renumber is equal to Tray 3, and as a result, the source assignments for the multi-purpose feeder and Tray 3 are swapped as a result of the renumbering. Thus, requests for source number assignment 4 are converted to requests for the multi-purpose feeder and requests for source number assignment 5 are converted to requests for Tray 2.
This method of renumbering trays using Tray 1 renumber, multi-purpose feeder renumber and last tray renumber has significant drawbacks. First, there is significant complexity in swapping source number assignments using the tray renumbering assignment command. Second, not all source assignments may be changed. This can be a significant drawback if a printer has five paper sources. Third, two sources had to be swapped, that is, one source assignment could not be changed independent of other source assignments. Fourth, it is difficult to determine which source number assignments have been swapped, if a record of the source number assignments is not kept on hard copy. Given these limitations, there are situations where it is not possible to reconfigure a replacement printer's logical tray selection algorithm to meet the specification of the target printer even though sufficient physical media input sources are available.